title: The effects of pH, salt and bond stiffness on charged dendrimers.
abstract: We have performed molecular dynamics simulations of charged dendrimers with various charge distributions, and including both rigid and soft bonds between the monomers. Whereas the rigid bonds result in a shell-like structure, the soft bonds lead to a larger dendrimer size and a more homogeneous monomer distribution. The measured density profiles of counter-ions and co-ions are compared with those stemming from Poisson-Boltzmann theory. The latter is in very good agreement with simulations for the soft-bond model, whereas for rigid bonds, significant discrepancies arise caused by the fact that Poisson-Boltzmann theory neglects finite-size ion effects. The addition of monovalent salt has no significant influence on the behavior of the dendrimers.
authors.affiliation: Institute of Theoretical Physics, Heinrich Heine University of Düssedorf, Universitätsstrasse 1, D-40225 Düsseldorf, Germany. sebastian@thphy.uni-duesseldorf.de
authors.forename: Sebastian
authors.initials: S
authors.lastname: Huissmann
authors.forename: Aaron
authors.initials: A
authors.lastname: Wynveen
authors.forename: Christos N
authors.initials: CN
authors.lastname: Likos
authors.forename: Ronald
authors.initials: R
authors.lastname: Blaak
mesh_terms: D000465:Algorithms; D003198:Computer Simulation; D050091:Dendrimers / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D007477:Ions; D015233:Models, Statistical; D008968:Molecular Conformation; D016011:Normal Distribution; D016012:Poisson Distribution; D012492:Salts / Q000737:chemistry*; D012997:Solvents / Q000737:chemistry; D055672:Static Electricity
chemical_list: D050091:Dendrimers; D007477:Ions; D012492:Salts; D012997:Solvents